Introduce ARM CP reg accessors

bindings/python/unicorn/unicorn_py3/arch/arm.py

@@ -10,7 +10,7 @@
 from unicorn import arm_const as const
 
 # newly introduced unicorn imports
-from ..unicorn import Uc
+from ..unicorn import Uc, check_maxbits
 from .types import UcTupledReg, UcReg128
 
 ARMCPReg = Tuple[int, int, int, int, int, int, int, int]
@@ -56,5 +56,55 @@ def _select_reg_class(cls, reg_id: int) -> Type:
 
         return next((c for rng, c in reg_class if reg_id in rng), cls._DEFAULT_REGTYPE)
 
+    # to learn more about accessing aarch32 coprocessor registers, refer to:
+    # https://developer.arm.com/documentation/ddi0601/latest/AArch32-Registers
+
+    def cpr_read(self, coproc: int, opc1: int, crn: int, crm: int, opc2: int, el: int, is_64: bool) -> int:
+        """Read a coprocessor register value.
+
+        Args:
+            coproc  : coprocessor to access, value varies between 0 and 15
+            opc1    : opcode 1, value varies between 0 and 7
+            crn     : coprocessor register to access (CRn), value varies between 0 and 15
+            crm     : additional coprocessor register to access (CRm), value varies between 0 and 15
+            opc2    : opcode 2, value varies between 0 and 7
+            el      : the exception level the coprocessor register belongs to, value varies between 0 and 3
+            is_64   : indicates whether this is a 64-bit register
+
+        Returns: value of coprocessor register
+        """
+
+        assert check_maxbits(coproc, 4)
+        assert check_maxbits(opc1,   3)
+        assert check_maxbits(crn,    4)
+        assert check_maxbits(crm,    4)
+        assert check_maxbits(opc2,   3)
+        assert check_maxbits(el,     2)  # note that unicorn currently supports only EL0 and EL1
+
+        return self.reg_read(const.UC_ARM_REG_CP_REG, (coproc, int(is_64), el, crn, crm, opc1, opc2))
+
+    def cpr_write(self, coproc: int, opc1: int, crn: int, crm: int, opc2: int, el: int, is_64: bool, value: int) -> None:
+        """Write a coprocessor register value.
+
+        Args:
+            coproc  : coprocessor to access, value varies between 0 and 15
+            opc1    : opcode 1, value varies between 0 and 7
+            crn     : coprocessor register to access (CRn), value varies between 0 and 15
+            crm     : additional coprocessor register to access (CRm), value varies between 0 and 15
+            opc2    : opcode 2, value varies between 0 and 7
+            el      : the exception level the coprocessor register belongs to, value varies between 0 and 3
+            is_64   : indicates whether this is a 64-bit register
+            value   : value to write
+        """
+
+        assert check_maxbits(coproc, 4)
+        assert check_maxbits(opc1,   3)
+        assert check_maxbits(crn,    4)
+        assert check_maxbits(crm,    4)
+        assert check_maxbits(opc2,   3)
+        assert check_maxbits(el,     2)  # note that unicorn currently supports only EL0 and EL1
+
+        self.reg_write(const.UC_ARM_REG_CP_REG, (coproc, int(is_64), el, crn, crm, opc1, opc2, value))
+
 
 __all__ = ['UcRegCP', 'UcAArch32']

bindings/python/unicorn/unicorn_py3/arch/arm64.py

@@ -11,7 +11,7 @@
 from unicorn.unicorn_const import UC_ERR_ARG, UC_HOOK_INSN
 
 # newly introduced unicorn imports
-from ..unicorn import Uc, UcError, uccallback
+from ..unicorn import Uc, UcError, uccallback, check_maxbits
 from .types import uc_engine, UcTupledReg, UcReg128
 
 ARM64CPReg = Tuple[int, int, int, int, int, int]
@@ -100,5 +100,49 @@ def _select_reg_class(cls, reg_id: int) -> Type:
 
         return next((c for rng, c in reg_class if reg_id in rng), cls._DEFAULT_REGTYPE)
 
+    # to learn more about accessing aarch64 coprocessor registers, refer to:
+    # https://developer.arm.com/documentation/ddi0601/latest/AArch64-Registers
+
+    def cpr_read(self, op0: int, op1: int, crn: int, crm: int, op2: int) -> int:
+        """Read a coprocessor register value.
+
+        Args:
+            op0		: opcode 0, value varies between 0 and 3
+            op1 	: opcode 1, value varies between 0 and 7
+            crn 	: coprocessor register to access (CRn), value varies between 0 and 15
+            crm 	: additional coprocessor register to access (CRm), value varies between 0 and 15
+            op2 	: opcode 2, value varies between 0 and 7
+
+        Returns: value of coprocessor register
+        """
+
+        assert check_maxbits(op0, 2)
+        assert check_maxbits(op1, 3)
+        assert check_maxbits(crn, 4)
+        assert check_maxbits(crm, 4)
+        assert check_maxbits(op2, 3)
+
+        return self.reg_read(const.UC_ARM64_REG_CP_REG, (crn, crm, op0, op1, op2))
+
+    def cpr_write(self, op0: int, op1: int, crn: int, crm: int, op2: int, value: int) -> None:
+        """Write a coprocessor register value.
+
+        Args:
+            op0		: opcode 0, value varies between 0 and 3
+            op1 	: opcode 1, value varies between 0 and 7
+            crn 	: coprocessor register to access (CRn), value varies between 0 and 15
+            crm 	: additional coprocessor register to access (CRm), value varies between 0 and 15
+            op2 	: opcode 2, value varies between 0 and 7
+            value	: value to write
+        """
+
+        assert check_maxbits(op0, 2)
+        assert check_maxbits(op1, 3)
+        assert check_maxbits(crn, 4)
+        assert check_maxbits(crm, 4)
+        assert check_maxbits(op2, 3)
+
+        self.reg_write(const.UC_ARM64_REG_CP_REG, (crn, crm, op0, op1, op2, value))
+
 
 __all__ = ['UcRegCP64', 'UcAArch64']

bindings/python/unicorn/unicorn_py3/unicorn.py

@@ -43,7 +43,6 @@ def __load_uc_lib() -> ctypes.CDLL:
 
     import inspect
     import os
-
     import sys
 
     loaded_dlls = set()
@@ -209,6 +208,19 @@ def __set_prototype(fname: str, restype: Type[ctypes._CData], *argtypes: Type[ct
 MMIO_WRITE_CFUNC = ctypes.CFUNCTYPE(None, uc_engine, ctypes.c_uint64, ctypes.c_uint, ctypes.c_uint64, ctypes.c_void_p)
 
 
+def check_maxbits(value: int, nbits: int) -> bool:
+    """Verify that a certain value may be represented with at most `nbits` bits.
+
+    Args:
+        value : numeric value to check
+        nbits : max number of bits allowed
+
+    Returns: `True` if `value` is represented by at most `nbits` bits, `False` otherwise
+    """
+
+    return value & ~((1 << nbits) - 1) == 0
+
+
 class UcError(Exception):
     """Unicorn base exception.
 
@@ -1160,8 +1172,8 @@ def context_restore(self, context: UcContext) -> None:
 
     @staticmethod
     def __ctl_encode(ctl: int, op: int, nargs: int) -> int:
-        assert nargs and (nargs & ~0b1111) == 0, f'nargs must not exceed value of 15 (got {nargs})'
-        assert op and (op & ~0b11) == 0, f'op must not exceed value of 3 (got {op})'
+        assert nargs and check_maxbits(nargs, 4), f'nargs must not exceed value of 15 (got {nargs})'
+        assert op and check_maxbits(op, 2), f'op must not exceed value of 3 (got {op})'
 
         return (op << 30) | (nargs << 26) | ctl